1. Field of the Invention
The invention relates to a plastic protective tube or conduit arrangement for lines, preferably for cable harnesses in motor vehicles, comprising an annularly corrugated flexible plastic tube for receiving the lines, said tube having a longitudinal slit or slot for inserting the lines.
2. Description of the Prior Art
Such an arrangement is known from German OS No. 3,405,552 and comprises a corrugated flexible plastic tube which is longitudinally slit. In the region of the longitudinal slit the tube walls overlap each other and can be fastened together in press-stud manner by complementary interlockable means A cable harness or tree can be inserted into such a tube through the bent-open longitudinal slit; hereafter the longitudinal slit is closed and the cable harness is protected by the tube from mechanical and chemical influences.
However, on laying round tight curves when the closed longitudinal slot is in an unfavourable position it can spring open again; it is also possible for the cable tree or harness to be damaged on the sharp longitudinal edges when introduced through the narrow longitudinal slit.
In addition, the wall thickness of such a plastic tube is relatively small due to the production methods; it may therefore happen that the known plastic tube is crushed by projecting edges or the like.
The disadvantage mentioned at the beginning can admittedly be overcome by longitudinal division of the tube into two half tubes as is known from German OS No. 2,304,852 but this latter known arrangement has the disadvantage that the cable harness or tree after insertion into one of the tube halves does not stay in the latter but must be additionally fixed before the other tube half is fitted.
If several tube portions are to be attached to a cable tree or harness and lie one behind the other a special connecting sleeve is necessary to avoid the cable being worn through by the tubes at the joint between said two tubes.
An advantage of the known conduit arrangement resides in that it has a substantially circular outer contour so that commercially available connecting fittings, connecting sleeves and the like can be employed.
A further advantage of the known arrangement is that projecting nipples which can be cut open are provided on the tube and branches of the cable tree or harness can be inserted into said nipples and thus need not be passed through the longitudinal slit. These branch positions must however be sealed with insulating tape or the like to prevent water or other liquids from reaching the interior of the conduit or tube arrangement.